Sex-limited inheritance in Lychnis dioica L. 275 



XBF. X bF = heterozygous broad-leafed females, 

 XbF.XbF = homozygous narrow-leafed females, 

 XBF.Xbf = heterozygous broad-leafed males, 

 XbF .Xbf = homozygous narrow-leafed males. 



It will be noted that this expectation differs from that for the Fa 

 in only one point, namely, in the appearance of homozygous narrow- 

 leafed females instead of homozygous broad-leafed females. I confidently 

 predicted the fulfilment of these expectations and laid plans for the 

 extensive use of narrow-leafed females in subsequent breeding; imagine 

 my astonishment at the results presented in Table I. 



Table L 

 Genetic formula: XBF.XbFX XbF.Xbf. 



It is seen that the two expected rosette-types, broad and narrow, 

 occurred in each family, in ratios not more divergent from the expected 

 1:1, than might well be accounted for by the obviously less vigorous 

 constitution of the angusti folia-form, but in the entire series of families, 

 ^gating 1097 individuals, there were only 2 females! No adequate 

 :planation can be offered at the present time for this remarkable result, 

 must be made the subject of further experimental inquiry. That there 



